Desiccating apparatus.



s. H. BUNNELL,

DESICCATING APPARATUS. 'APPucAHoN FILED MAY 9, 1914.

Pqtented J1me 1, 1915.

2 SHEETS'.SHEET 1- WITNESSES Q Q 7 l/VI/E/VTOR @kBJ BY ATTOR/VE 5.

S. H. BUNNELL.

DESICCATING APPARATUS. APPLICATMN FILED MAY 9, 19M.

Patented J ans 1, 1915.

2 SHEETS-SHEET 2.

WITNESSES HQ WM STERLING H. BUNNELL, OE NEW CANAAN, CONNECTICUT, ASSIGNOR TO THE GRISCOM- i r m RUSSELL COMPANY, A CORPORATION OF DELAWARE.

DESICCAT ING APPARATUS.

I Specification of Letters Patent.

Patented June 1, 1915.

Application filed May 9, 1914. Serial No. 837,360.

T (ZZZ whom it may concern:

Be it known that I, STERLING H. Bun- NELL, a citizen of the United States, residing 1n New Canaan, county of Fairfield, and

. btate of Connecticut, have invented certain able others skilled in the art to which it appertains to make and use the same.

This invention relates to desiccating ape paratus adapted particularly for use in the production of a dried, uncooked milk pow der which is readily soluble in water.

It has been proposed heretofore, to desiccate milk by spraying it into a moving body of heated air so as to vaporize the liquid content of the milk and immediately thereafter to coolthe moving body of air together with the vapor and the milk product carried thereby so as toprevent injury to the dried product.

The present invention is directed to the v provision of an improved form of apparatus for desiccating in this manner wherebythe powdered product may be readily produced in substantial quantities, whereby greater efiiciency and convenience in operation are attained and whereby waste of the liquid material is greatlyreduced.

One of the primary features of the invention resides in the provision of means for preventing the liquid milk sprayed into the apparatus from being carried into contact with the walls of the apparatus and means for utilizing centrifugal force'for facilitating the collection of the dried product.

In accordance with the invention, the heated air which is to receive the sprayed liquid is forced into a suitable chamber at a tangentthereto so that it will set up a. whirling motion Within the chamber. The liquid product is air current and is carried around thereby so that movement of the liquid out to the wall of the chamber in a substantially direct path is precluded. Instead, the liquid is carried around with the air and is subjected to the heat thereof so that the liquid content becomes vaporized. The whirling motion of the air is continued beyond the point where the liquid is sprayed into it so that the solid particles maintain this circular movement at the time when the air is cooled so as to prevent injury to the dried product. By reason sprayed into this whirling of this, the dried productis subjected to centrifugal force and moves outwardly to the wall of the chamber, thus facilitating its collection. I

The cooling of the body of air is preferably eifected by admitting an additional supply of air at a substantially lower temperature and the admission of such air may be eflected in such a way as will increase the circular motion of the air carrying the dried product.

The inclosing chamber may have sloping sidewalls at the region where the cooler air is admitted and the dried product moving outwardly into contact with ing 'walls will drop down along the walls so that it may 'be'collected in a suitable receptacle provided in a position to receive it. The preferred embodiment of the inventlon is illustrated in the accompanying drawings, in which- Figure 1 is a sectional elevation. of the apparatus, Fig. 2 is a top view thereof and Fig. 3 is a sectional detail view on line 33 of Fig. 1.

Referring to these drawings, 4 indicates a receptacle or chamber into which the heated air and the liquid product to be desiccated are admitted. I

The liquid product is sprayed into the chamber in any suitable manner and I have indicated a sprayer at 5 diagrammatically, this being shownas arranged in a vertical position so as to atomize the liquid upward Vertically in the chamber 4. The heated air is forced into the chamber 4 at a tangent to that chamber so that it will setup a Whirling motion within the chamber 4-.

The conduit through which this heated air is admitted is shown at 6 and by reference to Fig. 2, it will be seen that this conduit 6 enters the chamber & at a tangent thereto.

' Air is supplied to the conduit 6 by a centrifugal blower 7, the air passing from this blower through a suitable heating apparatus. In the drawings, the blower 7 is shown as operated by an engines. The passage way leading from the blower 7 is divided so as to form two conduits 9' and 10. In the conduit 10 is a suitable heating appara-' tus, this being shown in the present instance as consisting of a coil of pipe 11 which is supplied with exhaust steam from the engine 8 through the pipe 12. Of course, the coil 11 may be supplied with live steam or with exhaust steam from one or more these slop- I sources other than or additional to the engine 8.

suitable valves whereby the flow of air from .the blower 7 may beregulated so that the desired proportions of that air will pass The apparatus is provided with through the duct 10 which is provided with the heating coil and through the duct 9 which is not provided with heating means.

Also, a valve is provided whereby air may be passed through the coil 11 and into the duct 9. For this purpose, a valve is shown at 13 by which the entrance to the duct 9 may be closed to any desired degree. A

.second valve 14 controls the entrance to the duct 10 so that the entrance to that duct may be closed to any desired degree. -A third valve is shown at 15 controlling a passage between the ducts 9 and 10 at a pointbeyond the coil 11. This valve 15 may be positioned so as to open the passageway controlled thereby to any desired degree and it is shown as adapted to be moved to a position for closing the duct 10 partially or wholly. and leaving the opening into the duct 9 wide open.

The duct 10 leads to a heater whereby the air'may be heated to any desired degree before being admitted to the desiccating apparatus through the conduit 6. In the present instance, this heater for the air is shown as combined with a boiler which may be utilized-to supply steam to the engine 8 and other apparatus in use at the plant.

The boiler and heater are of the vertical tubular form consisting 'ofa cylindrical casing 16 having a multiplicity of vertical tubes 17 and 18 arranged therein. At the base of 'the structure is a combustion chamber 19 intov which the flame of an oil burner is directed. The hot gases from the combustion chamber rise through the tubes 17 and the tubes 18 and pass out through the stack 20, giving .up their heat to the water surrounding the tubes 17 and the air surrounding the tubes 18. The tubes 18 are preferably-arranged in alinement with the tubes 17 to facilitate cleaning thereof.

shown in Fig. 1..

The receptacle 4 is preferably offrustoconical shape as shown'in Fig. 1 and its upper, larger end is open to receive the lowerend of the apparatus for introducing the supply of cooler air. This apparatus consists of a hood 24, preferably of cylin-,

drical form, closed'at'its lower end at 25 and having a plurality of openings'at distributed points around its cylindrical wall. The bottom 25 of the hood is preferably of conical shape as shown and extends but a short distance below the upper end of the receptacle 4. Preferably, means are pro.- vided for controlling the size of the openings in the hood 24 so that the size of the exit for the air from the hood 24 may be regulated as desired. Also, the walls of the exit orexits from the hood 24 are preferably formed so as to give a circular motion to the air issuing from the hood 24. For this purpose, the openings for the air are preferably provided in the manner shown in Fig. 3 by cutting the metal of the hood 24 and bending the cut portions outwardly as shown at 26'at an incline toa radius of the hood 24. The vane for controlling the "size of the exits from the hood 24consists of a cylinder 27 of sheet metal fitting snugly within the hood 24 and movable therein about its axis. This cylinder 27 has openings in thewall thereof corresponding in number and position 'to the openings in the hood 24 and formed in the same manner as that above described. The outwardly directed walls 28 of the vane or regulator project through the openings in the wall of the hood 24 as shown in Fig. 3 so that these outwardly bent portions 28 assist in directing the air issuing from the hood in a circular course.

Surrounding the hood 24 is a wall 29 whose sides. slope inwardly toward the bottom thereof. This wall 29 is mounted in position with its lower end a short distance below the upper end of the receptacle 4 and this lower, smaller end of the wall 29 is of a diameter slightly in excess of the diameter of the upper end of receptacle 4.

An annular tray 30 is secured to the wall of thereceptacle 4 a'short distance below the upper end thereof so that the bottom .of the tray is a'little belowthe lower end of the wall 29 and sothat the upright wall of the tray 30 lies outside of the lower end of the wall 29.

In thebottom wall of the tray 30 are one or more openings adapted to be closed by removable plugs 31 which plugs may be removed to permit the discharge of the powdered product collecting in the tray 30 into receptacles 32 which may be supported upon a shelf 33. I

The upper end of the collecting apparatus may be closed by a fabric 34, this being secured at one edge to the upper end of the wall 29 and at the other edge to the hood 24.

In the operation of the apparatus, the

blower is set in motion to supply relatively hot air to the lower end of the col- .lector and cooler air to the hood 24, the temperature .of the latter being regulated by passing more or less of it through coil 11 by means of valves 13, 14: and 15. entering the bottom of the collector through the conduit 6 is directed into the receptacle l tangentially so that it sets up a whirling motion therein and the milk or other product to be desiccated is atomized into this whirling body of air by the sprayer 5. The air admitted to the apparatus through the conduit 6 is preferably heated to a temperature of about 300 F.. This may readily be done by controlling the supply of fuel to the boiler 16. When the atomized liquid comes in contact with this heated air, the liquid content thereof is vaporized and effecterial to be desiccated is insured by, the circular motion of the air within the receptacle 4 which holds the material sprayed into it in suspension for a longer time. Also, this motion of the air prevents waste which would result from the. movement of the atomized liquid into contact with the walls of the receptacle 4. The air, the vapor and the dried product carried thereby move up wardly within the receptacle 4 until they arrive within the space between the wall 29 and the hood 2%. At this time, the air and the product carried thereby are cooled by coming in contact with the cooler air issuing from the hood 24, this air being supplied by the blower 7 through the duct 9. The temperature of this air with reference to the outside temperature so that it will not cause precipitation of the vapor in the air around the hood 24 but will rapidly reduce the temperature of that air to such a degree that the dried product will not be injured. The circular motion of the air in, the chamber is continued after that air enters the space surrounding the hood 2L, and is augmented by the air issuing from the hood 24 which air is directed in a circular path by the inclined walls 26 and 28 of the hood 24 and vane 27. By reason of this circular motion of the air, the dried particles carried thereby are caused to move outwardly by centrifugal force until finally they come in contact with the inclined wall 29 and having done so, these particles drop down along the inclined wall 29 and accumulate in the tray 30. The air and the vapor carried thereby finally escape through the fabric 34: and such particles of the dried product as continue to be carried thereby are caught by this fabric. At intervals during the operation of the apparatus, the fabric 1 34: is shaken so'as to cause particles of the dried product caught thereby to drop vertically upon the M1129 and into the tray 30. The accumulated dry product in tray 30 effects a seal of the space between he lower end of wall '29 and the upperend of receptacle 4. 7 When sufficient powder has accumulated in tray 30, it may be passed the openings in the bottom thereof The airtive vaporization of the liquid in the mamust be regulated ried thereby heated air entering means for spraying throughand in o receptacle 32. The proper amount of air to be admitted through the hood 2* depends upon conditions which very and this amount may therefore be regulated as required by movement of the vane so as to adjust the size of the openings through which the air passes from the hood.

I claim:

1. A desiccating apparatus comprising the combination of a receptacle, means for admitting heated. air to the receptacle and causing the air to set up a circular motion within the receptacle, a sprayer for spraying the material to be desiccated into the air within the receptacle and means for rapidly cooling the air and the product carried. thereby; substantially as described.

2. A. desiccating apparatus comprising the combination of a receptacle, means for ad-- mitting air to the receptacle and causing the air to set up a circular motion'within the receptacle, a spraying apparatus for spraying the material to be desiccated into the moving body'of air and means for cooling the air and the product carried thereby while continuing the circular movement of the air; substantially as described.

3. A desiccatingapparatus comprising the combination of a receptacle, means for forc- 27 within the hood ing the heated air'into the receptacle to establish a circular movement of the air within the receptacle, a sprayer for sprayingthe material to be desiccated into the moving body of air and means for introducing cooler airinto the moving body of heated air for rapidly cooling the same; substantially as described.

desiccating apparatus comprising the combination of a receptacle circular in cross-sections, means for forcing heated air tangentially into the receptacle to' establish a circular motion ceptacle, a sprayer for spraying the material to be desiccated into the moving body of air within the receptacle and means for rapidly cooling the air and the product carsubstantially as described.

5. A desiccating apparatus comprising the combination of a receptacle circular in cross 7 sections,

'means for forcing heated air tangentially into the receptacle, spraying apparatus for spraying the material. to be desiccated into the moving body of air and means for cooling the carried thereby While continuing the circular movement of the air; substantially as described;

6. A esiccating apparatus comprising the combination of a i into same tangentially, the material to be desiccated into the receptacle, means for intro ducing cooler air into, the receptacle at a .point distant from v the conduit and said receptacle, a duct for' 1 of the a1r within the reair and the product spraying means, the wall of thereceptacle v surrounding said last-named means being inclined, and a receiver for the dried product at the lower end of saidinclined wall; substantially as described.

' .7. A desiccating apparatus comprising the combination of a receptacle, a conduit for heated air entering the same substantially tangentially, spraying apparatus for spraying the material to be desiccated into the receptacle and a duct for cooling air entering the receptacle at a point distant from said conduit and said sprayingapparatus; substantially as described.

' 8. A desiccating apparatus comprising'the combination of'a receptacle circular in crosssections, a c'onduitfor heated air entering the same tangentially, a spraying apparatus for spraying the material .to be desiccatedinto the receptacle and a duct for cooling air enter ng the receptacle and concentric therewith and having radially disposed outlets; substantially as described.

9. A desiccating apparatus comprising the combination of a receptacle, a conduit for heated air entering the same substantially tangentially, a duct for cooling air entering the receptacle at a point distant from said conduit and having radially disposed outlets and means for adjusting the size of the outlets from said duct; substantially as described.

10. A desiccating apparatus comprising the combination of a receptacle'which is circular in cross=sections and larger at one end than at the other, a conduit entering the receptacle tangentially near the smaller endthereof, means for spraying the material to be desiccated into the receptacle, and a duct entering the larger end of the receptacle concentric with the receptacle and having a plurality of radially disposed outlets; substantially as described.

- 11. "A desiccating apparatus comprising the combinationof a receptacle, a conduit for heated air entering the same substantially tangentially, a duct for cooling air entering the receptacle at a point distant from said conduit and having radially dis.- v

pos'ed outlets, the wall ofthe receptacle surrounding the outlets from said duct being inclined. and a receiver for the dried product at the lower end of said inclined wall; substantially as described.

12. A desiccating apparatus comprising the combination of a receptacle, a conduit for heated'alr entering the same substantially tangentially, a duct for cooling air' entering the receptacle at a point distant from said conduit, a blowing apparatus for supplying air to said conduit and said. duct," a heater and means for conveying air from I the blower through theheater to either the conduit or the duct; substantially as described.

13. A desiccating apparatus comprising the combination of a receptacle, means for forcing heated air substantially tangentially into the receptacle to establish a circular motion of the air within the receptacle, a spraying apparatus for spraying the material to be desiccated into the moving body of air within the receptacle, and means for introducingcooler air into thereceptacle in a direction to continue the circular motion of the air therein to effect rapid cooling of the heated air and the product carried thereby; substantially as described.

14. A desiccating apparatus comprising the combination of a desiccating chamber, means for admitting heated air to one part of the chamber, means for spraying the material to be desiccated into the air thus admitted and means for admitting cooler air to another part of the chamber to rapidly 4 cool the heated air therein and the product carried by that air; substantially as described.

15, A desiccating apparatus comprising the combination of a desiccating chamber which is larger at one end than at the other,

means for admitting heated air to the tric" with the receptacle and adapted to convey cooler airto the receptacle; substantially as described.

17. A desiccating apparatus comprising the combination of a receptacle of circular form larger at one end than at the other, means for admitting heated air to the smaller end of the receptacle, a sprayer for spraying the material to bedesiccated into the receptacle and a hoodentering the larger end of the receptacle concentric therewith and prouided with radial openings for admitting cooler air to the receptacle; substantially as described. i

In testimony whereof I afiix my signature in presence of two witnesses.

STERLING H. BUNNELL.

lVitnesses WM. S. EmrUNDs.

. VIOLET C. Bnxxn'rr. 

